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Myelodysplastic syndromes (MDS) and their progression to secondary acute myeloid leukemia (sAML) are associated with an altered protein expression including extracellular matrix (ECM) components thereby promoting an inflammatory environment. Since the role of the proteoglycan biglycan (BGN) as an inflammatory mediator has not yet been investigated in both diseases and might play a role in disease progression, its expression and/or function was determined in cell lines and bone marrow biopsies (BMBs) of MDS and sAML patients and subpopulations of MDS stem cells by Western blot and immunohistochemistry. The bone marrow (BM) microenvironment was analyzed by multispectral imaging, patients' survival by Cox regression. ROC curves were assessed for diagnostic value of BGN. All cell lines showed a strong BGN surface expression in contrast to only marginal expression levels in mononuclear cells and CD34+ cells from healthy donors. In the MDS-L cell line, CD34-CD33+ and CD34+CD33+ blast subpopulations exhibited a differential BGN surface detection. Increased BGN mediated inflammasome activity of CD34-CD33+TLR4+ cells was observed, which was inhibited by direct targeting of BGN or NLRP3. BGN was heterogeneously expressed in BMBs of MDS and sAML, but was not detected in control biopsies. BGN expression in BMBs positively correlated with MUM1+ and CD8+, but negatively with CD33+TLR4+ cell infiltration and was accompanied by a decreased progression-free survival of MDS patients. BGN-mediated inflammasome activation appears to be a crucial mechanism in MDS pathogenesis implicating its use as suitable biomarker and potential therapeutic target.

Background:A higher incidence of COVID-19 infection was demonstrated in cancer patients, including lung cancer patients. This study was conducted to get insights into the enhanced frequency of COVID-19 infection in cancer.Methods:Using different bioinformatics tools, the expression and methylation patterns of ACE2 and TMPRSS2 were analyzed in healthy and malignant tissues, focusing on lung adenocarcinoma and data were correlated to clinical parameters and smoking history.Results:ACE2 and TMPRSS2 were heterogeneously expressed across 36 healthy tissues with the highest expression levels in digestive, urinary and reproductive organs, while the overall analysis of 72 paired tissues demonstrated significantly lower expression levels of ACE2 in cancer tissues when compared to normal counterparts. In contrast, ACE2, but not TMPRSS2, was overexpressed in LUAD, which inversely correlated to the promoter methylation. This upregulation of ACE2 was age-dependent in LUAD, but not in normal lung tissues. TMPRSS2 expression in non-neoplastic lung tissues was heterogeneous and dependent on sex and smoking history, while it was downregulated in LUAD of smokers. Cancer progression was associated with a decreased TMPRSS2 but unaltered ACE2. In contrast, ACE2 and TMPRSS2 of lung metastases derived from different cancer subtypes was higher than organ metastases of other sites. TMPRSS2, but not ACE2, was associated with LUAD patients’ survival.Conclusions:Comprehensive molecular analyses revealed a heterogeneous and distinct expression and/or methylation profile of ACE2 and TMPRSS2 in healthy lung vs. LUAD tissues across sex, age and smoking history and might have implications for COVID-19 disease.

Background: The small leucine-rich proteoglycans (SLRPs) biglycan (BGN) and decorin (DCN) linked with sulfated glycosaminoglycan (GAG) chains exhibit oncogenic or tumor suppressive potentials depending on the cellular context and association with GAGs. Objective: We hypothesized that structural alterations and expression levels of BGN, DCN and their associated chondroitin sulfate (CS) polymerizing enzymes, dermatan sulfate (DS) epimerases and various sulfatases might be correlated with the tumor (sub)type and patients’ survival. Methods: We acquired breast cancer (BC) and glioma patients’ datasets from cBioPortal and R2 Genomics. Structural alterations and the expression pattern of CS polymerizing enzymes, DS epimerases and carbohydrate sulfotransferases (CHST) were compared to that of BGN and DCN and correlated to their clinical relevance. Results: In BC, no mutations, but amplifications (0.2 – 2.1 %) and deletions (0.05 – 0.4 %) were found in BGN, DCN and CS/DS enzymes. In contrast, missense and/or truncated mutations (0.1 – 0.5 %), but a reduced amplification rate (0 – 1.5 %) were found in glioma. When compared to BC, the structural abnormalities caused altered mRNA expression levels of BGN, DCN, GAG synthesizing enzymes and CHST. Mutations in SLPRs, CHSY1, CHST4 and CHSY3 were correlated with a poor prognosis in glioma, while lack of mutations and copy number variations in the SLRPs, CHSY3, CHST15 and DSE displayed an increased survival in BC. Conclusion: A distinct association of BGN and DCN with CHST, CS polymerizing enzymes and DS epimerases was found in BC and glioma. Thus, a unique pattern of structural alterations and expression, which has clinical relevance, was found for PGs and GAG synthesizing enzymes and CHST in BC and glioma, which might help to identify high-risk patients and to develop personalized therapeutics.

Background The extracellular matrix protein biglycan (BGN) plays an essential role in matrix assembly, cellular migration, adhesion, proliferation and apoptosis. Recently, BGN expression has been shown to be impaired upon HER-2/neu overexpression, which was associated with an up-regulation of MHC class I surface expression. However, there exists no information about the link between K-RAS-mediated immune escape and BGN expression. Methods In vitro models of human K-RAS G12V transformed mouse fibroblasts and two human colorectal carcinoma (CRC) cell lines carrying a K-RAS G12V mutation (RKO and SW480) were used for the analysis of BGN expression by qPCR and Western blot. At the same time, the major histocompatibility complex (MHC) class I surface expression, as well as CD4+ and CD8+ cells, were determined by flow cytometry. The different K-RAS G12V cells and respective controls were stably transfected with BGN. Growth properties were analyzed by proliferation, migration and invasion assays. Luciferase reporter assays were used to determine the transcriptional regulation of MHC class I APM components. Tumorgenicity of BGN transfectants in comparison to control cells was evaluated by injection of respective transfectants s.c. into mice and tumor growth was monitored over time. Results Both murine and human K-RAS G12V cells express low levels of BGN compared to control cells. Overexpression of BGN caused an inhibition of cell proliferation, a diminished anchorage-independent growth and a reduced migration rate. The altered in vitro growth properties of BGNhigh K-RAS G12V+ correlated with a delayed tumor growth and a reduced frequency of tumor formation in vivo. Restoration of BGN expression increased the expression of decorin as well as enhanced MHC class I expression in K-RAS G12V-transformed cells. This is due to a BGN-induced transcriptional upregulation of major components of the MHC class I antigen processing machinery (APM), such as the transporter associated with antigen processing TAP1, TAP2 and LMP2, in BGN transfectants of K-RAS G12V+ cells. The results were further supported by the fact that mice bearing tumors induced by BGNhigh K-RAS G12V+ cells showed a reduced MHC class I expression, which was associated with an enhanced frequency of CD8+ and CD4+ cells in the peripheral blood. Conclusions Our data provide evidence that (i) proteoglycan signatures are modulated by K-RAS G12V transformation, (ii) loss of proteoglycan expression is directly or indirectly involved in immune escape of K-RAS G12V overexpressing tumor cells and (iii) BGN overexpression and enhanced basal decorin expression results in altered growth properties of K-RAS G12V cells. Thus, the reduced migration rate and restoration of MHC class I surface expression by BGN or other proteoglycans are important features for their anti-tumorigenic properties in K-RAS G12-transformed tumor cells including colorectal cancers. Acknowledgements The project is supported by Wilhelm-Sander-Stiftung (No: 2019.076.1). Consent Not applicable

There exists increasing evidence that people with preceding medical conditions, such as diabetes and cancer, have a higher risk of infection with SARS-CoV-2 and are more vulnerable to severe disease. To get insights into the possible role of the immune system upon COVID-19 infection, 2811 genes of the gene ontology term “immune system process GO: 0002376” were selected for coexpression analysis of the human targets of SARS-CoV-2 (HT-SARS-CoV-2) ACE2, TMPRSS2, and FURIN in tissue samples from patients with cancer and diabetes mellitus. The network between HT-SARS-CoV-2 and immune system process genes was analyzed based on functional protein associations using STRING. In addition, STITCH was employed to determine druggable targets. DPP4 was the only immune system process gene, which was coexpressed with the three HT-SARS-CoV-2 genes, while eight other immune genes were at least coexpressed with two HT-SARS-CoV-2 genes. STRING analysis between immune and HT-SARS-CoV-2 genes plotted 19 associations of which there were eight common networking genes in mixed healthy (323) and pan-cancer (11003) tissues in addition to normal (87), cancer (90), and diabetic (128) pancreatic tissues. Using this approach, three commonly applicable druggable connections between HT-SARS-CoV-2 and immune system process genes were identified. These include positive associations of ACE2—DPP4 and TMPRSS2—SRC as well as a negative association of FURIN with ADAM17. Furthermore, 16 drugs were extracted from STITCH (score

The underlying molecular mechanisms of the aberrant expression of components of the HLA class I antigen processing and presentation machinery (APM) in tumors leading to evasion from T cell-mediated immune surveillance could be due to posttranscriptional regulation mediated by microRNAs (miRs). So far, some miRs controlling the expression of different APM components have been identified. Using in silico analysis and an miR enrichment protocol in combination with small RNA sequencing, miR-26b-5p and miR-21-3p were postulated to target the 3&prime, untranslated region (UTR) of the peptide transporter TAP1, which was confirmed by high free binding energy and dual luciferase reporter assays. Overexpression of miR-26b-5p and miR-21-3p in melanoma cells downregulated the TAP1 protein and reduced expression of HLA class I cell surface antigens, which could be reverted by miR inhibitors. Moreover, miR-26b-5p overexpression induced a decreased T cell recognition. Furthermore, an inverse expression of miR-26b-5p and miR-21-3p with TAP1 was found in primary melanoma lesions, which was linked with the frequency of CD8+ T cell infiltration. Thus, miR-26-5p and miR-21-3p are involved in the HLA class I-mediated immune escape and might be used as biomarkers or therapeutic targets for HLA class Ilow melanoma cells.

Background There exists increasing evidence that people with preceding medical conditions, such as asthma, diabetes, cancers and heart disease, have a higher risk of infection with SARS-CoV-2 and are more vulnerable to severe disease.Methods To get insights into the role of the immune system upon COVID-19 infection, 2811 genes of the gene ontology term “immune system process GO: 0002376” were selected for analyses. The immune system genes potentially co-expressed with the human targets of SARS-CoV-2 (HT-SARS-CoV-2) ACE2, TMPRSS2 and FURIN were determined in tissue samples from patients with cancer and diabetes mellitus. The network between HT-SARS-CoV-2 and immune system process genes was analyzed based on functional protein associations using STRING. In addition, STITCH was employed to determine druggable targets.Results DPP4 was the only immune system process gene, which was coexpressed with the three HT-SARS-CoV-2 genes, while eight other immune genes were at least co-expressed with two HT-SARS-CoV-2 genes. STRING analysis between immune and HT-SARS-CoV-2 genes plotted 19 associations of 8 commonly networking genes in mixed healthy (323) and cancer (11003) tissues in addition to normal (87), cancer (90) and diabetic (128) pancreatic tissues. Using this approach, three druggable connections between HT-SARS-CoV-2 and immune system process genes were identified. They include positive associations of ACE2 - DPP4 and TMPRSS2 – SRC as well as a negative association of FURIN with ADAM17. Furthermore, the 16 drugs were extracted from STITCH (score Conclusions This bioinformatics pipeline identified for the first time an immunological network associated with COVID-19 infection thereby postulating novel therapeutic opportunities.

The recent COVID-19 outbreak in China led to a worldwide pandemic associated with a severe acute respiratory illness. A higher incidence of COVID-19 infection was demonstrated in cancer patients, including patients with lung cancer. This study was conducted to get insights into the reasons for this enhanced frequency of COVID-19 infection. Methods: Using different bioinformatic tools, the expression and methylation pattern of ACE2 and TMPRSS2 gene were analyzed in healthy and malignant tissues with a focus on lung adenocarcinoma (LUAD) and correlated to clinical parameters and smoking history. Results: ACE2 and TMPRSS2 were heterogeneously expressed across 36 healthy tissues with the highest expression in digestive, urinary and reproductive organs, while their expression was significantly lower in 36 cancer tissues. In LUAD, ACE2, but not TMPRSS2 was overexpressed, which inversely correlated to the promoter methylation. An age-dependent upregulation of ACE2 expression was found in LUAD compared to normal lung tissues. In a healthy lung, TMPRSS2 expression was dependent on sex and smoking history and downregulated in LUAD of smokers. Cancer progression was associated with decreased TMPRSS2, but unaltered ACE2 expression, while ACE2 expression in lung metastases of different cancers was higher than in metastasis of other sites. TMPRSS2, but not ACE2 expression, was associated with LUAD patients’ survival. Conclusions: Comprehensive molecular analyses revealed a heterogeneous, distinct expression and methylation profile of ACE2 and TMPRSS2 in healthy lung vs LUAD tissues across sex, age and smoking history, which is associated with clinical parameters and might have implications for COVID-19 disease.

Immunotherapy aims to activate the immune system to fight cancer in a very specific and targeted manner. Despite the success of different immunotherapeutic strategies, in particular antibodies directed against checkpoints as well as adoptive T-cell therapy, the response of patients is limited in different types of cancers. This attributes to escape of the tumor from immune surveillance and development of acquired resistances during therapy. In this review, the different evasion and resistance mechanisms that limit the efficacy of immunotherapies targeting tumor-associated antigens presented by major histocompatibility complex molecules on the surface of the malignant cells are summarized. Overcoming these escape mechanisms is a great challenge, but might lead to a better clinical outcome of patients and is therefore currently a major focus of research.

Background Garlic has lost its ability to form seeds in the course of its domestication. Therefore, the germplasm storage via cryopreservation is increasingly applied. The progression of the various steps within the cryopreservation procedure is accompanied by declining survival rates of the explants. Much of the recent work on cryo-stress has been focussed on osmotic and cold stress components. However, two decades after invention of garlic cryopreservation, the function of metabolites and oxygen in and around the cryopreserved tissues is still largely obscure. Methods In this study, hypoxia was characterized in cryopreservation of garlic with oxygen sensors and amino acid metabolism. Furthermore, malondialdehyde, soluble sugars and ammonium were quantified to demonstrate the influence of cryo-stress in declining survival rates. Results To better understand the possible reasons for a reduction in the survival rate at the subsequent steps of cryopreservation, the concentration of amino acids, ammonium, γ-aminobutyric acid (GABA), soluble sugars, malondialdehyde (MDA), and oxygen were measured in garlic shoot tips undergoing cryopreservation. Using microsensors, a very low oxygen concentration (